将多个excel文件导入python pandas并将它们连接成一个数据帧

I would like to read several excel files from a directory into pandas and concatenate them into one big dataframe. I have not been able to figure it out though. I need some help with the for loop and building a concatenated dataframe: Here is what I have so far:

我想从目录中读取几个excel文件到pandas并将它们连接成一个大数据帧。我虽然无法弄明白。我需要一些关于for循环和构建连接数据帧的帮助：这是我到目前为止所拥有的：

import sys
import csv
import glob
import pandas as pd

# get data file names
path =r'C:\DRO\DCL_rawdata_files\excelfiles'
filenames = glob.glob(path + "/*.xlsx")

dfs = []

for df in dfs: 
    xl_file = pd.ExcelFile(filenames)
    df=xl_file.parse('Sheet1')
    dfs.concat(df, ignore_index=True)

2 个解决方案

#1

As mentioned in the comments, one error you are making is that you are looping over an empty list.

正如评论中所提到的，您正在犯的一个错误是您正在循环一个空列表。

Here is how I would do it, using an example of having 5 identical Excel files that are appended one after another.

这是我将如何做到这一点，使用一个接一个地附加5个相同的Excel文件的例子。

(1) Imports:

（1）进口：

import os
import pandas as pd

(2) List files:

（2）列表文件：

path = os.getcwd()
files = os.listdir(path)
files

Output:

输出：

['.DS_Store',
 '.ipynb_checkpoints',
 '.localized',
 'Screen Shot 2013-12-28 at 7.15.45 PM.png',
 'test1 2.xls',
 'test1 3.xls',
 'test1 4.xls',
 'test1 5.xls',
 'test1.xls',
 'Untitled0.ipynb',
 'Werewolf Modelling',
 '~$Random Numbers.xlsx']

(3) Pick out 'xls' files:

（3）选出'xls'文件：

files_xls = [f for f in files if f[-3:] == 'xls']
files_xls

Output:

输出：

['test1 2.xls', 'test1 3.xls', 'test1 4.xls', 'test1 5.xls', 'test1.xls']

(4) Initialize empty dataframe:

（4）初始化空数据帧：

df = pd.DataFrame()

(5) Loop over list of files to append to empty dataframe:

（5）循环到要附加到空数据帧的文件列表：

for f in files_xls:
    data = pd.read_excel(f, 'Sheet1')
    df = df.append(data)

(6) Enjoy your new dataframe. :-)

（6）享受您的新数据框。 :-)

df

Output:

输出：

  Result  Sample
0      a       1
1      b       2
2      c       3
3      d       4
4      e       5
5      f       6
6      g       7
7      h       8
8      i       9
9      j      10
0      a       1
1      b       2
2      c       3
3      d       4
4      e       5
5      f       6
6      g       7
7      h       8
8      i       9
9      j      10
0      a       1
1      b       2
2      c       3
3      d       4
4      e       5
5      f       6
6      g       7
7      h       8
8      i       9
9      j      10
0      a       1
1      b       2
2      c       3
3      d       4
4      e       5
5      f       6
6      g       7
7      h       8
8      i       9
9      j      10
0      a       1
1      b       2
2      c       3
3      d       4
4      e       5
5      f       6
6      g       7
7      h       8
8      i       9
9      j      10

#2

this works with python 2.x

这适用于python 2.x.

be in the directory where the Excel files are

位于Excel文件所在的目录中

see http://pbpython.com/excel-file-combine.html

请参阅http://pbpython.com/excel-file-combine.html

import numpy as np
import pandas as pd
import glob
all_data = pd.DataFrame()
for f in glob.glob("*.xlsx"):
    df = pd.read_excel(f)
    all_data = all_data.append(df,ignore_index=True)

# now save the data frame
writer = pd.ExcelWriter('output.xlsx')
all_data.to_excel(writer,'sheet1')
writer.save()